Control mechanism



Patented Jan. 26, 1937 UNITED STATES CONTROL llIECHANISMv victor w. Kamath, south Bend, Ind., signor to Bragg-Kliesrath Corporation, South Bend, Ind., a corporation of Indiana Application Aug-ust 13, 1934, Serial No. 739,623

1 Claim.

This invention relates to power actuators of the dilerential uid pressure actuated type, and is illustrated as embodied in a novel vacuum actuy ated device to assist in the operation of the brake 5 and in holding the clutch of an automotive vehicle.

An object of the invention is to provide a simple and effective power device, in which all the moving parts are enclosed and protected, and which is adapted for universal use with a minimum of designing and experimenting.

My invention therefore contemplates vthe use of a novel power cylinder having a closure at` its end to which is secured a conduit, preferably a flexible IBowden type conduit. Within the cylinder is a power member such as a piston or its equivalent, to which is connected one end of a tension element extending through the closure and into and through the conduit, the other end being connected to assist in the operation of the brake or clutch.

Anothergobject of the invention is the provision of a single-ended cylinder mounted upon the dashboard of the vehicle and operably connected 5 to assist in the application of the brake and clutch pedal by a Bowden cable control.

The above and other objects and advantages of this invention will be apparent from the following detailed description, togethr with the i1- lustrative embodiment thereof, shown in the accompanying drawing, which is submitted for purposes of illustration only and is not intended to define the scope of the invention, reference being had for that purpose to the subjoined Claim.

In the drawing, wherein similar reference characters refer to similar partsthroughout the several views: y f

Figure 1 is a diagrammatic sectional view of a portion of an automotive vehicleequipped with a device of the present invention;

Figure 2 is a longitudinal sectional view of the valve member shown in Figure 1; and

Figure 3 is a longitudinal sectional view of the power actuator shown in Figure 1.

Referring more particularly to Figure 1 there is shown a portion of an automotive vehicle com- Y' prising an engine lll equipped with amanifold I2 which, during the operation of the engine,

forms a source of subatmospheric pressure.

The subatmospheric pressure existing in the manifold is employed to actuate a power cylinder I4 to assist the operator in applying a brake and clutch control pedal I6 pivotally mounted at I8 and extending through the floor-boards 20.

A control valve 22, more particularly described hereinafter, is interposed in a connection, comprising a rod 24, connecting the control pedal I6 withy a crank 26, operably connected to a cross shaft 2B, which may be connected to actuate the 5 brakes in a known manner when it is desired to employ the device of the present invention to operate the brakes ofthe vehicle.

If it is desired to actuate the clutch by this mechanism, a crank 21. may be xed to the pedal 10 lI6 to disengage the clutch, represented diagrammatically at 29. When the pedal I6 is depressed the crank 21 is rotated in the counterclockwise direction to compress the spring 3l and permit the separation of the frictional plates of the 15 clutch (shown diagrammatically) in a known manner.

A conduit 30 connects a portion 0f the valve 22 with the manifold, and another conduit 32 connects the, power actuator I4 to another por- `20 tion of the .valve 22, so that the power actuatorA I may be alternately subjected to the subatmospheric pressure existing in the manifold or to atmospheric pressure, depending upon the position of the valve as hereinafter described. 1

The illustrated valve includes a casing 46 connected 'to the rod 24, and closed at the front side by a plate 48 with a iiexible diaphragm 50 arranged therebetween. A circular ledge 52, separating the manifold and power-device connec- 30 tions 30 and 32,-is formed on the valve casing, and normally engages the ldiaphragm 50, which is held thereagainst by a metal washer 54 or the like urged toward the-right by a spring 56.

In this position the manifold connection 30 is 35 shut off by'engagement of the diaphragm 50 with the ledge 52, and conduit 32 is in communication with the atmosphere through openings 58 in the diaphragm and in the Washer 54, these openings being at all times in communication with open'- 40 ings 60 in plate 48, these latter openings being` protected' by baille members 62 secured to plate 48.

If now the pedal I6 is depressed, a two-part threadedly-connected plunger 64, slidable on the 45 shaft connection 66 secured permanently in the casing 46, and connected to the center of diaphragm 50, moves to the left until it engages a' stop 68 threaded on connection 66. 'I'his movement is suilicient to cause a part 10 on the end 50 of plunger 64 to engage the diaphragm 50 and cut oii 'the connection'to the atmosphere, at the same time pushing the diaphragm away from the ledge 52 and establishing a connection between conduit 30 and conduit 32. Thus with the '56 pedal depressed, communication is established between the engine manifold and the conduit 32.

The conduit 32 opens into the single-ended cylinder 90, drawn or stamped from sheet steel, and mounted on a bracket or the like 92 carried by the dashboard 94, facing downwardly. The lower end of the cylinder has a closure |14 provided with air vents protected by baffles |18. A Bowden-type :dexibleV conduit |82 is connected at its upper end to the closure |14, and at its lower end to a fixed bracket 96 adjacent the brake or clutch pedal i6.

Within the cylinder is a power member such as a piston connected to a tension element ISS passing through tubular tting |84 carried by closure |18, and through the conduit |82, and connected at its lower end to the pedal I6.

The operation of this device is as follows, assuming that the engine is running and that the operator wishes to disengage the clutch, and apply the brakes. He 'depresses lever I6 thereby disengaging the clutch and at the same time moving the rod 24 to the left as viewed in Figure 1, and by means of the plunger 64 and the connection Si, moving the part 10 of the valve 22 to the left, engaging diaphragm 50 and removing it from circular ledge 52, so that the subatmos# pheric pressure existing in the manifold I2 may be passed through conduit 30, over circular ledge l2, through conduit 32, to evacuate the cylinder Sl of the power actuator |4. lAs thecyiinder is evacuated, piston I" moves upwardly as viewed in Figure 3, thereby exerting a pull on tension element |86, and exerting a pull on lever I6, tending to rotate it in the counterclockwise direction' Continued rotation of 1 as viewed in Eigure 1. the lever I6 causes rotation of the shaft 28 which applies the brakes. The power actuator is thus employed to assist in operating the lever i6. The operator is thus relieved of the greater portion of the physical labor in actuating the clutch.

The device is also very convenient and serviceapplication, Serial No. 559,987, led August 28,

Having thus described the invention what I claim as new and desire to obtain by Letters Patent is:

In a vehicle having a prime mover including a source of vacuum, and a manually operable member, braking means comprising a cross shaft operated by said member, clutch means operated by saidmember, a linkage interconnecting said member and the cross shaft, power means for assisting the operation of said manually operable member comprising ax chamber, a conduit connecting said chamber to said source of vacuum,

-a valve in said conduit and interposed in said linkage so as to be controlled by said manually operable member, said chamber having a movable wall actuated bydiiferences in vacuum in the chamber, a exible tension member connecting said movable wall to said manually operable member, and a sheath enclosing said tension member.

l VICTOR W. KLIESRATH. 

